Then it's a crap ad but a nice piece of visual art
I know the one you mean though and I can't remember what it's for either...
Sand's a really beautiful meduim for 'painting'. When I was studying for my graphics degree I went to the Royal Academy to see an Exhibition for 'The Art of Tibet' which was really wonderful with gorgeous colours, mostly with textiles but they had several monks there 'performing' live over a huge low table with coloured sands and that was similar but done in silence (well the monks were anyway) was really tranquil and the abstracts they made were stunning - watched them for over an hour.
Having talent thankfully isn't all about the show and making a song and dance about it all
Often true art is only about what come's from inside of you, the sort that mattersat least, and I expect that's why the crowd was so moved there - something about 1946 wasn't it at the end so I'm assuming it was some kind of national tragedy after WW2?